What is a parked domain in email?

A parked domain is a registered domain name that is not currently being used for a website or email service. Instead, it often points to a placeholder page or a domain registrar's default page. Emails sent to addresses at parked domains commonly bounce or are directed to spam traps , making them dangerous for email senders.

How do suspicious email addresses affect email deliverability?

Suspicious email addresses, like those with misspellings or at parked domains, can severely harm your email deliverability. Sending to them increases your bounce rate, signals poor list hygiene to ISPs, and can lead to your sending IP or domain being blacklisted (blocklisted) . This, in turn, can cause your legitimate emails to land in spam folders or be rejected entirely.

Can simple typos like 'gmaii.com' be dangerous?

Yes, even simple typos like 'gmaii.com' instead of 'gmail.com' can be very dangerous. These are examples of typosquatting, where malicious actors register domains that are common misspellings of legitimate ones. Emails sent to these domains can end up in spam traps or be used for phishing attempts, making them a significant risk to your sender reputation.

What tools can help identify suspicious email addresses?

You can use a WHOIS lookup service to check a domain's registration and nameserver information. Additionally, you can check the email's authentication records (SPF, DKIM, DMARC) to verify its legitimacy. Email validation services can also help identify and filter out suspicious or fake email addresses .

Should I ever email an address with a suspicious domain?

No, you should avoid sending emails to addresses with suspicious domains, especially those associated with parked domains or known typosquatting tactics. These addresses are likely spam traps or invalid addresses, and sending to them can significantly damage your sender reputation and lead to blocklisting.

How to identify and handle suspicious email addresses like @123gmail.com? - Sender reputation - Email deliverability - Knowledge base

Email is the lifeblood of modern communication, but with its widespread use comes the persistent threat of suspicious activities. One common pattern that raises red flags for me and other deliverability professionals is email addresses that look slightly off, like @123gmail.com or @yourcompany.info. These seemingly minor variations can indicate a significant problem, ranging from simple typos to sophisticated phishing attempts or spam traps.

Failing to identify and address such suspicious email addresses can severely impact your sender reputation, leading to lower inbox placement rates and potentially getting your legitimate emails blocklisted. Maintaining a clean and healthy email list is crucial for successful email campaigns and ensuring your messages reach their intended recipients.

Identifying suspicious domains and addresses

A common characteristic of suspicious email addresses is their resemblance to legitimate domains, but with subtle alterations. This is often a tactic known as typosquatting or domain squatting, where malicious actors register domains that are common misspellings or variations of popular services, like adding numbers or letters to a well-known domain. For instance, an address like john.doe@123gmail.com immediately suggests a fraudulent origin because 123gmail.com is not an official

Gmail domain. These domains are frequently set up as spam traps designed to catch spammers and invalid senders.

To spot such addresses, examine the domain name (the part after the '@' symbol) closely. Look for subtle misspellings, additional numbers or characters, or unusual top-level domains (TLDs) that don't match the sender's apparent identity. For example, if an email claims to be from a well-known bank but the domain is bankofamerica.co instead of bankofamerica.com, it's likely suspicious. This applies to both inbound emails you receive and addresses on your own mailing lists. For a more comprehensive understanding of these patterns, consider reading about suspicious email domains.

Another common indicator is when a domain is parked. This means the domain is registered but not actively used for a website or email service, often pointing to a domain registrar's default page. Emails sent to addresses on parked domains frequently bounce or, worse, land in a spam trap. You can typically use a WHOIS lookup service to check a domain's registration details, including its age, registrar, and nameserver information. A very new domain or one registered with an obscure registrar that resembles a well-known one is a strong warning sign.

Technical red flags and validation methods

Beyond visual cues, technical checks are indispensable for identifying suspicious email addresses and preventing phishing emails. A legitimate sender's domain should have properly configured email authentication records such as SPF, DKIM, and DMARC. These records help email servers verify that the sender is authorized to send mail from that domain. A missing or improperly configured record for a seemingly official domain is a major red flag.

You can check these records using various online tools. For example, if you see an email from support@microsoft.help, you would want to verify that microsoft.help has valid SPF, DKIM, and DMARC records. The absence of these, or misconfigurations, strongly indicates a potentially fraudulent email.

Additionally, observing engagement history for email addresses on your list can provide vital clues. Addresses that never open, click, or respond to emails, especially if they have unusual domain patterns, are likely low-quality or fake. These high-risk email addresses can be detrimental to your sender reputation over time.

I also pay close attention to the IP addresses from which subscribers are acquired, especially through web forms. A sudden influx of registrations from a single IP address, or from known proxy/VPN services, might indicate bot-generated email addresses. This can be a sign of bot email addresses attempting to infiltrate your list.

Legitimate signs

Consistent branding: Matches the sender's official domain exactly.
Proper authentication: Has valid SPF, DKIM, and DMARC records.
Expected content: Message content, links, and tone align with known communications.

Suspicious indicators

Typosquatting/variants: Slight misspellings or additional characters (e.g., @123gmail.com).
Generic/random characters: Usernames or domains that appear algorithmically generated.
Missing DNS records: Lack of SPF, DKIM, or DMARC for the sending domain.
Unsolicited nature: Email appears without prior interaction or context.

Handling suspicious email addresses

Once identified, dealing with suspicious email addresses effectively is crucial for maintaining a healthy email list and protecting your deliverability. For addresses like @123gmail.com or those associated with parked domains, immediate removal is often the best course of action. Continuing to send emails to such addresses will only increase your bounce rates and signal to ISPs that you are not managing your list properly, harming your sender reputation. Consider these high-risk addresses as detrimental to your email program.

Implementing preventative measures at the point of data collection is equally important. Using double opt-in for all new subscribers ensures that only genuinely interested recipients confirm their subscription. This simple step can significantly reduce the number of fake or generated email addresses entering your list. Additionally, CAPTCHA challenges on your forms can deter automated bots from submitting invalid email addresses.

Regular list hygiene is an ongoing process, not a one-time fix. Consistently monitor your email list for unengaged subscribers, high bounce rates, and addresses that exhibit suspicious patterns. Tools that offer blocklist monitoring can alert you if your domain or IP is listed due to sending to poor-quality addresses, enabling you to take corrective action promptly. Being proactive helps mitigate potential damage before it escalates.

The dangers of ignoring suspicious addresses

Damaged sender reputation: ISPs will view you as a sender of low-quality or unsolicited mail.
Increased bounce rates: Sending to non-existent addresses inflates your bounce rate, signaling poor list management.
Blocklisting: Your sending IP or domain may end up on a blacklist (blocklist), preventing delivery to major inboxes.
Wasted resources: Sending emails to invalid addresses consumes bandwidth and can incur costs with your ESP.

Proactive measures for improved deliverability

To truly safeguard your email deliverability, it's essential to move beyond reactive measures and embrace proactive strategies. A key aspect of this is the continuous maintenance of a clean and engaged email list. Regularly review subscriber activity, remove unengaged contacts, and ensure your acquisition methods discourage the submission of spam and low-quality email addresses.

Implementing a strong DMARC policy (like p=quarantine or p=reject) is another crucial step. DMARC helps protect your domain from being spoofed by malicious actors who might create suspicious-looking addresses using your brand name. By enforcing a DMARC policy, you instruct receiving mail servers on how to handle emails that fail authentication, ensuring that only legitimate emails from your domain reach the inbox. Check out simple DMARC examples for guidance on getting started.

Finally, regularly audit your subscriber acquisition sources. If you notice a particular source or channel generating a high volume of suspicious or bot-generated email addresses, it's time to re-evaluate that source. It could be an indication of fraudulent sign-ups or a compromised lead generation method. By being vigilant and proactive, you can significantly reduce your exposure to suspicious email addresses and improve your overall email deliverability. For more information, the FTC offers guidance on recognizing and avoiding phishing scams.

Views from the trenches

Best practices

Validate email data at the point of collection to prevent junk addresses from entering your list.

Implement double opt-in for all new subscribers to ensure genuine interest and consent.

Regularly clean your email lists of unengaged, bounced, or suspicious addresses.

Monitor your domain's SPF, DKIM, and DMARC records for proper configuration and alignment.

Use blocklist monitoring tools to stay informed about your domain and IP reputation.

Common pitfalls

Trusting the 'from' address without verifying the underlying domain and authentication status.

Failing to differentiate between legitimate major domains and typosquatted or parked domains.

Ignoring high bounce rates or low engagement from segments of your email list.

Not implementing DMARC policies that enforce rejection or quarantine for unauthenticated emails.

Collecting email addresses from unverified or low-quality lead generation sources.

Expert tips

Email addresses at parked domains almost always bounce or are spam traps and should be removed.

A spike in fake or suspicious emails submitted via web forms often indicates bot activity or poor acquisition.

Review your historical engagement data to pinpoint which contacts are truly active and valuable.

Verify the domain's WHOIS and nameserver information to determine if it's a legitimate or suspicious entity.

Do not send to any email address where the domain looks like a slightly altered version of a popular ESP, as these are often malicious.

Marketer view

Marketer from Email Geeks says email addresses resembling '123gmail.com' are usually garbage data from someone trying to provide invalid information.

2019-09-17 - Email Geeks

Marketer view

Marketer from Email Geeks says such addresses are likely trap domains and indicate a need for better data validation processes.

2019-09-17 - Email Geeks

Maintaining a clean and secure email ecosystem

Navigating the complexities of email security and deliverability means always being on the lookout for suspicious email addresses. By understanding the signs of dubious domains, implementing robust validation processes, and diligently maintaining your email lists, you can significantly enhance your sender reputation and ensure your messages consistently reach the inbox.

Treating your email list as a valuable asset that requires continuous care and attention is paramount. It’s an ongoing commitment, but one that pays dividends in improved deliverability, better engagement, and a stronger connection with your audience. Remember, a clean list is a healthy list, and a healthy list drives results.